Reversible direct current motor



Dec. 23, 1952 G. KRONACHER REVERSIBLE DIRECT CURRENT MOTOR Filed Jan. 2]. 1950 v|/6/vr0l 6546420 Mon 44.45

Patented Dec. 23, 1952 "REVERSIBLE DIRECT CURRENT MOTOR Gerald Kronac'her, .New York, N. Y.,:ass,ignor to ..=Air Associates,I-Inc., .Tetcrhoro, N. J .,,.av corpo- -rationfitNewlJersey 2ApplicationiJanuary -21, 1950, "Serial N o." 132K814 2 Claims.

This invention relates. tora'; reversible motorand has particularreferenceto a;reversible. directqcurrent motor whichis rotatable atta relativelyl high speed in one direction and at 'a. :.relatively low speed in the opposite direction and which: maintainsi substantially the same: speed ratio with refferenceto the torque in both directions from noload to stall.

The invention "has in-view :a reversible direct current motor having .field exciting windings which when' energized :efiect rotationoin one direction of :the 1 motor atzhigh :speed substantially as :a' series "motor andiintthe 'oppositeidirection at Iow. speed as a compound motor. Still another objectxof'the invention istoprovide-a reversibledirect current'xmotor inwhich certain .of the 'field exciting windings are arranged to provide opposite excitation to thereby produce a weak resultant excitation of the motor to effect rotation in one direction athigh'speed and in which :all of the field exciting'windings are'arranged toi'produce'a strong resultant excitationandzrotate the motor inlthe opposite direction atlow speed.

'stillizanoither object ofthe invention is to provide a reversible motor which is-adapted to be rotatedinxopposite directions by the "movement of a single pole double-throwswitch With. the: foregoing and other objects in view, reference is nowmade to the followin specification .and accompanying drawings in which the preferred embodiment 1 of the :i-nvention is illustrated.

In the drawings:

Fig-1 is1;aschematic view'of the wiring diagram of a reversible direct current motor constructed in accordancewith the invention.

) Fig. 2 is a schematic view of they wiringapplied to a two 'pole motor.

In the embodiment of the invention illustrated in the drawings, a wiring diagram-bra reversible direct current motor is schematically shownin Fig. 1 thereof having three "exciting field windingsIO,-II and I2. The exciting'field windings lfl and II have substantially the same number of turns while the-exciting field'winding I2 ismade up of a relatively lesser number of turns. Two resistor coils I3 and I4 are also provided Which are wound upon a brake core so as to magnetize in the same direction for attracting an armature (not shown) to produce a braking action on the motor.

The exciting field winding II is connected at one end with a terminal l5 of a single pole doublethrow switch I6 and at its opposite end the said is connected in parallel with the exciting field winding I2 and with .thearmature A through the brushes I! and I8. The switch I6 is connected with the positive side S of a source of electric power, while the brush I8 is connected with the negative side R of said source of electric power.

Connected in this manner, the windings will polarize as indicated by the solid arrows when the switch I6 is moved to closed relation with the terminal I5 thereof while vthebroken arrows indicate thepolarization of the windings when the switch ismoved to close the circuit with the terminal l9 thereof. It will be seen that the excitation produced by the flow of current through the windings III and II from the terminal I9 oppose eachothertand being substantially of the same number of turns produce no magnetic field. The excitation produced by the windings I2 sets up a weak field so that the motor runs at high'speed in one direction. When the switch I6 is thrown to close the circuit with the terminal I5, the excitation produced by the flow of current through the windings I0, .II andIzZ is cumulative sothat the motor: operates as a compound motor with a strong fieldturning the motor at low speed in .theopposite direction. The current. flowing throughsth'e winding I2 and the resistor coil I4 produces a voltage drop in the winding I I to lower the speed of themotor which is' most effective atno-load condition.

The invention is illustrated in Fig.2 of the drawings in its application to a two pole motor but which may be employed in a motor having any multiple sets of poles. usual frame 20 provided with poles 2| and 22 and havin an armatureA and the brushes I! and I8 ashereinbefore described. The winding I I is connected with the terminal I5 of the switch It by a conductor wire 24, the winding being arranged with one-half of the turns thereof, indicated by the reference character I Ia, wound upon the pole 2| while the other half of the turns, indicated by the reference character IIb, is wound upon the pole 22 and connected with the portion He by a conductor wire 25. The winding III) is connected to the brush ll of the motor by a conductor wire The motor includes the 3 28. The winding I is also connected with the terminal I 01 the switch I6 by the conductor wire 24 and the said winding is arranged with onehalf of the turns thereof, indicated by the reference character Illa, wound upon the pole 2I while the other half thereof, indicated by the reference character IIlb, is wound upon the pole 22 and connected with the portion Ilia by a conductor wire 21. The portion lflb of said winding is connected with one end of the resistor coil I3 by a conductor wire 28, the opposite end of the resistor coil I3 being connected with the brush I8 by a con-1 ductor wire 29. The winding I2 is connected with the terminal I9 of the switch I6 by means of a conductor wire 30, the said winding being arranged with one-half of the turns thereof, indicated by the reference character I241, wound 4 said switch terminals to produce when connected with the first mentioned terminal cumulative excitation of said first, second and third mentioned windings to cause the motor to operate as a compound motor and the armature to turn at low speed in one direction, and to produce when the switch means is connected with the second mentioned terminal opposite. excitation of said first and third mentioned windings and the second mentioned winding bein in series with the armature to thereby cause the motor to operate as a series motor and the armature to rotate at high speed in the opposite direction.

2. IA reversible direct current motor having an armature, and a field member provided with at least two poles", a continuous field exciting winding wound in serieson said field poles and conon the pole 22 while the other half thereof, in-

dicated by the reference character I2b, is wound on the pole 2| and connected with the portion Illa thereof by a conductor wire 3I. The portion IZb of the winding I2 is connected by a conductor wire 32 with the brush I! of the motor. The conductor wire leading from the terminal I9 is connected with one end of the resistor coil l4 while the opposite end of the resistor coil I4 is connected by the conductor wire 29 with the brush I8 of the motor.

When the switch I-6 is moved to closed relation with the terminal I9, the excitation coil I2 is in series with the armature and the excitation coils I0 and I I and the resistor coil I3 are in series and are shunted across the armature with the coils IO and II functioning to neutralize each other. When the switch I6 is moved to closed relation with the terminal I5, the excitation coil I2 and the resistor coil I4 are in series and the same are shunted across the armature, the excitation coil I0 and the resistor coil I3 are in series and are shunted across the terminal 15 and the brush it and the coil I I is in series with the armature, the coils I0 and I I producin a cumulative excitation.

What is claimed is:

- 1. A reversible direct current motor having an armature and a field member provided with at least two poles, a continuous field exciting winding wound in series on said field poles and connected on one side with one of the poles of the armature and on the other side with a terminal of a switch, a second continuous field exciting winding wound in series on said field poles and connected on one side with the other terminal of said' switch and on the opposite side with'the same pole of the armature as the first mentioned winding, a third continuous field exciting winding wound in series on said field poles and connected on one side with the first mentioned terminal of said switch and on the other side with the pole of the armature opposite to that with which the first and second mentioned windings are connected, said last mentioned armature pole being connected with said second mentioned winding through a resistance and being connected with one side of a source of current supply, switch means connected with the other side of said source of current supply and adapted to selectively engage nected on one side with one of the poles of the armature and on the other side with a terminal of a switch, a second continuous field exciting winding' wound in series on said-field'poles and connected on one side with the other terminal of said switch and on the opposite side with thesame pole of the armature as the first mentioned winding, and said second mentioned winding having a relatively lesser number of turns than said first mentioned winding, a third continuous field exciting winding wound in series on said field poles and connected on one side with the first mentioned terminal of said switch and 'on the other side with the polemof the armature opposite to that with which the first and second mentioned windings are connected, said last mentioned armature pole being connected with said second mentioned winding through a resistance and being connected with one side of a source of current supply, switch means connected with the other side of said source of current supply and adapted to selectively engage said switch terminals to produce when connected with the first mentioned terminal cumulative excitation of said first and second and third mentioned windings to cause the motor to operate as a compound motor and the armature to turn at low speed in one direction, and to produce when the switch means is connected with the second mentioned terminal opposite excitation of said first and third mentioned windings and the second mentioned winding being in series with the armature to thereby cause the motor to operate as a series-motor and the armature to rotate at high speedin the opposite direction, the motor operatspeed ratio with reference to torque from no.- load to stall.

ing in both directions at substantially the same UGERALD KRONACHER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Thomas Nov. 2, 1948 

